Add generic data structures querying (#13684)

* Query lookup plugin

* Add license and docstrings

* Add python3-ish imports

* Change query plugin type from lookup to filter

* Switch from dq to jsonpath_rw

* Add integration test for query filter

* Rename query filter to json_query

* Add jsonpath-rw

* Rename query filter to json_query

* Switch query implementation from jsonpath-rw to jmespath

lib/ansible/plugins/filter/json_query.py

@@ -0,0 +1,48 @@
+# (c) 2015, Filipe Niero Felisbino <filipenf@gmail.com>
+#
+# This file is part of Ansible
+#
+# Ansible is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# Ansible is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.
+
+from __future__ import (absolute_import, division, print_function)
+__metaclass__ = type
+
+from ansible.errors import AnsibleError
+from ansible.plugins.lookup import LookupBase
+from ansible.utils.listify import listify_lookup_plugin_terms
+
+try:
+    import jmespath
+    HAS_LIB = True
+except ImportError:
+    HAS_LIB = False
+
+
+def json_query(data, expr):
+    '''Query data using jmespath query language ( http://jmespath.org ). Example:
+    - debug: msg="{{ instance | json_query(tagged_instances[*].block_device_mapping.*.volume_id') }}"
+    '''
+    if not HAS_LIB:
+        raise AnsibleError('You need to install "jmespath" prior to running '
+                           'json_query filter')
+
+    return jmespath.search(expr, data)
+
+class FilterModule(object):
+    ''' Query filter '''
+
+    def filters(self):
+        return {
+            'json_query': json_query
+        }

test/integration/roles/test_filters/tasks/main.yml

@@ -40,8 +40,8 @@
   register: diff_result_9851
 
 - name: 9851 - verify generated file matches known good
-  assert:  
+  assert:
-    that: 
+    that:
         - 'diff_result_9851.stdout == ""'
 
 - name: fill in a basic template
@@ -56,9 +56,9 @@
   register: diff_result
 
 - name: verify templated file matches known good
-  assert:  
+  assert:
-    that: 
+    that:
-        - 'diff_result.stdout == ""' 
+        - 'diff_result.stdout == ""'
 
 - name: Verify human_readable
   assert:
@@ -77,3 +77,9 @@
         - "31 == ['x','y']|map('extract',{'x':42,'y':31})|list|last"
         - "'local' == ['localhost']|map('extract',hostvars,'ansible_connection')|list|first"
         - "'local' == ['localhost']|map('extract',hostvars,['ansible_connection'])|list|first"
+
+- name: Test json_query filter
+  assert:
+    that:
+      - "users | json_query('[*].hosts[].host') == ['host_a', 'host_b', 'host_c', 'host_d']"
+

test/integration/roles/test_filters/vars/main.yml

@@ -1,6 +1,18 @@
 some_structure:
   - "this is a list element"
-  - 
+  -
     this: "is a hash element in a list"
     warp: 9
     where: endor
+
+users:
+  - name: steve
+    hosts:
+      - host: host_a
+        password: abc
+      - host: host_b
+  - name: bill
+    hosts:
+      - host: host_c
+        password: default
+      - host: host_d

test/utils/shippable/integration.sh

@@ -85,6 +85,8 @@ container_id=$(docker run -d \
 
 show_environment
 
+docker exec "${container_id}" pip install jmespath
+
 if [ "${copy_source}" ]; then
     docker exec "${container_id}" cp -a "${test_shared_dir}" "${test_ansible_dir}"
 fi

test/utils/shippable/remote-integration.sh

@@ -44,7 +44,8 @@ pkg install -y \
 # TODO: bootstrap.sh should install these
 pip install \
     junit-xml \
-    virtualenv
+    virtualenv \
+    jmespath
 
 # FIXME: tests assume bash is in /bin/bash
 if [ ! -f /bin/bash ]; then